Automatic selector-switch.



C. A. W. HULTMAN- AUTOMATIC SELECTOR SWITCH. APPLICATION man wu's, W14.

1 1 86,908, Patented J une 13, 1916.

)W: WWW @M a e %MWA Mmm STA ii CARL AXEL WILHELM HULTMIAIT, F STOCKHOLM, SWEDEN.

AUTOMATIC SELECTOR-SWITCH.

Specification of Letters Patent. Patented Jung 13, 1916,

Application filed July 9, 1914. Serial No. 849,933.

To all 107mm mag concern:

Be it known that l, A121. Axnn VVILHELM lt'l'ULTMAN, a citizen of the Kingdom. of Sweden, residing at Stockholm, Sweden,

have invented new and useful improvements in Automatic Selector-Switches, of which the following is a specification.

My invention relates to automatic selector switches of the kind used in telephone exchange systems and in which rotatable and longitudinally movable means are provided to bring about the connections desired.

The object of this invention is to provide a simple and compactly arranged switch of ,15 the kind in which the lines end in fixed terminals and in which no movable terminals are used, the rotatable and longitudinally movable means being electrically independent oi the circuit of the fixed terminals and only adapted to bring said fixed termi nals into contact with each other.

The invention will be more particularly described and further features thereof pointed out by reference to the accompanying drawing which by Way of example illustrates, partially in vertical section, a selector embodying my invention.

Referring to the drawing, 1 is the shaft of the selector switch said shaft being elec- 3o trically independent of the circuits of the selector. The shaft 1 can be rotated by any Well-known driving means, as for instance by means of a driving shaft 8 rotating intermittently or continuously and journaled in a frame as, and bevel Wheels 9 and 10, the Wheel 9 being attached to the shaft 1 and the wheel 10 to the driving shaft 8, or I may use a step magnet for such purpose. The shaft supports two systems of arms 2,

4,0 2 by means of which the terminals to be actuated by the selector are acted upon. Said terminals consist of springs 3, 4t, 3 l arranged in two concentric groups at each ystem of arms. The springs 3, 4c etiect for it instance the connection of a number or" speaking Wires with a connecting Wire in/ the telephone oifice, Whereas by means of the springs 3 4: the testing wires belonging to 2 id "Jen-hing wires may be connected with 5G co-. .ponding Wire in the telephone office. shaft 1 is movable in longitudinal "irectioi-zi. Normally the shaft is in its up position with the gears 9, 10, out or: bat it is to be rotated it 18 lowered to a certain extent so as to bring the gears into mesh. Said movement in longitudinal direction may be efiected by means of a solenoid or an electromagnetic device or in any other manner. Thereby the sys tem of arms 2 Will be moved away from the inwardly bent ends of the contact springs 3 so that the arms cannot touch said springs whereas the arms 2 are always able to close the contacts 3 When the shaft is rotated. When the desired testing Wire has been found and the selector, on account thereoi has been stopped, the shaft 1 Will, by means of a coiled spring; 7, be moved axially to its original position so that the contacts of the speaking Wires correspond ing to the testing Wire found are closed.

Having now described my invention What I claim as new and desire to secure by Letters Patent is:

1. In a selector switch, the combination with a rotatable and longitudinally movable shaft and systems of arms mounted'thereon,

of two concentric rows of fixed terminals for each arm system, the terminals of the inner row being adapted to be operated by the corresponding arm system, Whereas the terminals of the outenrow are adapted to be engaged by the:corresponding terminal of the inner row when the latter are acted upon by the arms, said arms being electrically independent of the circuits of the terminals.

2. In a selector switch, the combination with a rotatable and longitudinally mov-.

able shaft and two systems of arms mounted thereon and electrically independent of the circuits of the selector, of twoconcentric rows of fixed terminals for each arm system, the terminals of the inner row corresponding to one arm system being adapted to be acted upon by said arm system during the rotation of the shaft Whereas the terminals of the inner row corresponding to the otherpresence of two subscribing witnesses.

CARL [\XEL WILHELM HULTMAN. l Vitnesses Jenn DELMAR, Gunman HOLMSTRfil-L 

